Does a large number of pups in a litter mean each pup will be smaller?

The number of puppies that any given dam has in a litter can be hugely variable – some dams will have just two or even one puppies, whilst it is not uncommon for others to have seven or eight as standard. Litter sizes can be much larger than this too, and over twenty pups in just one single litter is not unheard of!

There are a number of different factors that contribute to the eventual number of pups in any given litter, and this is something that is widely discussed by both veterinary professionals and dog owners alike. However, another valid question and one that gets a lot less attention is whether or not the number of pups in a litter contributes to the birthweight and size of the individual puppies, and the size they will grow to as an adult.

It is reasonable to assume that a very large litter will result in smaller individual puppies, and that a litter of just a couple of pups will result in those pups being larger – but what is the truth of the matter? In this article, we will explain whether or not a large number of pups in a litter will result in each pup being smaller or not, and why this is. Read on to learn more.

Do lots of pups in a litter mean the pups will be small?

The answer to this key question is somewhat surprising – a large number of pups is not one of the factors that are generally considered to affect the pup’s birthweights.

If a gestating litter contains a very large number of puppies – more than the dam’s body can physically support – then the chances are that some of the pups won’t make it to birth, instead potentially being reabsorbed by the dam’s body or being stillborn along with the rest of the live, healthy litter.

Very large litters tend to have increased risk factors for stillbirth and miscarriage, but they don’t usually result in each pup being smaller than normal. A runt or one or two noticeably smaller, weaker pups are more likely to occur in a large litter too, but this may just be because the contrast between the larger and stronger pups and the weakest ones is more noticeable when there are lots of other pups to compare them to.

When it comes to what happens after birth, one potential challenge of a large litter is that the dam won’t be able to produce enough milk for all of them to thrive, which can result in a slower than projected growth rate, and the risk of the weaker puppies not being able to get food when competing with stronger pups.

Supplementary feeding, and monitoring the growth and development of each puppy can help to counteract this effect.

Next, we will look at some of the factors that do actually affect the size of a litter and the puppies within it.

The size of the dam

Larger dog breeds, and particularly giant breeds, tend to have larger litters – both in terms of the number of pups born as well as of course the size of the puppies! The Great Dane in particular tends to have large litters as standard, with eight pups being common and over ten not being overly unusual.

The age of the dam

A dam in her prime and at the peak of her breeding age will be a dam most likely to have a large litter of healthy pups, and like for like across any given dog breed, the litter of a dam under the age of two or one that is approaching the start of old age is likely to have a smaller litter.

The dam’s health

A dam that is fit and healthy prior to mating and throughout her pregnancy will be able to give her pups the best possible start to life, and will have a greater chance of having a larger litter of larger pups in relation to the breed’s norms.

A dam that is ailing, that has a chronic health condition or a conformation defect that affects her general wellness and condition is less likely to have a large litter, more likely to have pups with problems, and at greater risk throughout mating, gestation and delivery.

Nutrition

Pregnant and nursing dams need a lot of food, and it must be good quality and nutritious in order to allow her and so, her pups, to thrive.

If your dam can’t get enough food or if it is not the right type of food, some of the pups she is carrying may not be viable, and poor nutrition in the nursing dam will often also mean that she won’t be able to produce enough milk to sustain all of her pups to weaning.

If you have any concerns about your dam either prior to mating, during gestation or after delivery – particularly in terms of the health of the pups, their birthweight and whether or not they are growing at an appropriate rate – talk to your vet for advice.